1 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU2 VTT – Technical research centre of Finland3 Aalto University, Department of Applied Physics4 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU
The use of carbon as support material for platinum nano-crystallites in polymer electrolyte fuel cells (PEFC) is a common method for increasing the electrochemical specific surface area (ECSA) of platinum. During fuel cell operation, the conditions that catalysts are subjected to lead to various forms of the ECSA degradation: By agglomeration of the platinum crystallites, Rietveld ripening or indirectly by corrosion of the carbon support. Graphitised carbon nanostructures like carbon nanotubes (CNTs), carbon nanofibres (CNFs), etc. are proposed as carbon support substitutes to avoid carbon corrosion, as the nanostructures are thermally and chemically more durable. The presented work describes the effects on surface defect of acid treated Showa Denko vapour grown carbon fibres (VGCF®/VGCF-H®). A selection of carbon fibres have been platinised and the differences of the oxygen reduction currents without mass transport effects are determined by Koutecký-Levich plots at 900 mV and 850 mV vs. RHE. The normalised kinetic currents of the differently pre-treated fibres are presented from room temperature measurements and elevated temperature measurements.